Paint compositions are well known to be available in a number of colors. The aesthetic appearance of surfaces coated with these paints, the ease of use, and the long term durability of painted surfaces are important considerations. Water based (e.g., latex paints) and oil-based paints are generally available. Hiding ability and contrast ratio are particularly important properties of a colored paint composition. Typically, oil-based paints are superior to latex paints in this regard.
Typical paint compositions include pigment, binder, liquid and additives. Pigments are used to provide color and opacity to paint. Pigments can be either chemically organic or inorganic. Titanium oxide is an example of a prime pigment used in latex and oil-based paints having a white color. Moreover, pigments also typically add hiding properties to paint. Extender pigments are added to improve certain properties (e.g., scrub, stain, and chalk resistance) and to provide bulk to reduce cost. Additives are included to improve various chemical and physical properties of the paint. The liquids carry the components of the paint composition. In latex paints, the liquid is usually water.
Currently available yellow and yellow-containing colored paints are well-known for poor hiding, if organic yellow pigments are used to bring up bright colors. When yellow pigments are tinted in paint, the shooting level of colorant determines the hiding of deep base paints. However, only a limited amount of colorant can be added to base paint without negatively impacting paint performance, such as surfactant leaching, block resistance, film hardness, color rub-off, etc. A high volume of solid yellow pigments is a key factor to improve hiding without diminishing paint performance. Due to the high oil absorption of organic pigment, it is very difficult to achieve high solid content in slurries.
Accordingly, there is a need for improved paint formulation that addresses the challenges for high solid yellow colorants.